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  • La sauvegarde automatique de canaux SPIP

    1er avril 2010, par

    Dans le cadre de la mise en place d’une plateforme ouverte, il est important pour les hébergeurs de pouvoir disposer de sauvegardes assez régulières pour parer à tout problème éventuel.
    Pour réaliser cette tâche on se base sur deux plugins SPIP : Saveauto qui permet une sauvegarde régulière de la base de donnée sous la forme d’un dump mysql (utilisable dans phpmyadmin) mes_fichiers_2 qui permet de réaliser une archive au format zip des données importantes du site (les documents, les éléments (...)

  • Installation en mode ferme

    4 février 2011, par

    Le mode ferme permet d’héberger plusieurs sites de type MediaSPIP en n’installant qu’une seule fois son noyau fonctionnel.
    C’est la méthode que nous utilisons sur cette même plateforme.
    L’utilisation en mode ferme nécessite de connaïtre un peu le mécanisme de SPIP contrairement à la version standalone qui ne nécessite pas réellement de connaissances spécifique puisque l’espace privé habituel de SPIP n’est plus utilisé.
    Dans un premier temps, vous devez avoir installé les mêmes fichiers que l’installation (...)

  • Keeping control of your media in your hands

    13 avril 2011, par

    The vocabulary used on this site and around MediaSPIP in general, aims to avoid reference to Web 2.0 and the companies that profit from media-sharing.
    While using MediaSPIP, you are invited to avoid using words like "Brand", "Cloud" and "Market".
    MediaSPIP is designed to facilitate the sharing of creative media online, while allowing authors to retain complete control of their work.
    MediaSPIP aims to be accessible to as many people as possible and development is based on expanding the (...)

Sur d’autres sites (8643)

  • ffmpeg minterpolate and rubberband - how to stretch audio to fit ?

    5 juin 2023, par bossturbo

    What is the best way to control the length of the audio and pitch shift using rubberband ?

    


    I tried setting 'asetpts=PTS*16' to match the video PTS, but it appears to be ignored. The only thing that seems to determine the length of the audio is rubberband pitch. Even 'tempo=0.0625' does not appear to do anything.

    


    I would like to be able to set the audio length to match the slower video section and set the pitch to whatever I want, like minimum 0.15 and have it stretch the audio length as needed.

    


    ffmpeg -ss 123.978571 -i "original-120fps.MP4" -filter_complex "
[0:v]trim=0:0.375,setpts=PTS-STARTPTS,minterpolate='fps=480',setpts=PTS*16[slowv]; 
[0:a]atrim=0:0.375,asetpts=PTS-STARTPTS,rubberband=pitch=0.08:tempo=0.0625[slowa];"
 -y -r 60 -map [slowv] -map [slowa] -preset veryfast "output.mp4"


    


    Finally, is there a good guide to using lib-rubberband ? FFmpeg docs for rubberband doesn't explain anything.

    


  • Extract individual macroblock types and their corresponding motion vectors [closed]

    14 mai 2023, par Prajit Kumar

    I need to make a pair for each macroblock from a frame of a video containing its type and motion vector.

    


    I extracted motion vectors by using the python module of mv-extractor.

    


    For macroblock type I used ffmpeg command : ffmpeg -threads 1 -debug 'mb_type' -i file.h264 -f null -

    


    The info received from ffmpeg command doesn't match with the location of motion vectors extracted (Macroblocks which are divided into smaller blocks of size 8X16 or 16X8 do not match with the info of macroblock size received in motion vector info). Also, the ffmpeg command for extracting macroblock type doesn't work properly on some videos.

    


    Can you please tell a more streamlined way of doing this task.

    


  • Different ffmpeg result after saving to png

    28 juillet 2023, par Kalev Maricq

    Saving images to PNG first seems to produce different ffmpeg encodes. Running this test code

    


    from PIL import Image
import cv2
import ffmpeg
import hashlib

ffmpeg.input('test.jpg').output('testff.png').run()
cv2.imwrite('testcv.png',cv2.imread('test.jpg'))
Image.open('test.jpg').save('testpil.png')

hashes=[]
for suf in ['.jpg','ff.png','cv.png','pil.png']:
    dest='test'+suf.replace('.','')+'.mp4'
    ffmpeg.input('test'+suf).output(dest).run()
    hashes.append(hashlib.file_digest(open(dest,'rb'),'md5').hexdigest())
    
print(hashes)


    


    I get
    
['a5b744a8ac0f6de9ec4de43ff737c46e'
    
,'ab62474f2160899e064ba24890047372'
    
,'baa788d5e4ef212ab610b8b5cf7772cb'
    
,'baa788d5e4ef212ab610b8b5cf7772cb']

    


    As you can see, the only two that match are the cv2 and pillow conversions, and none of them match the original. In terms of file size, the results that passed to png first seem to be about 10% smaller than the direct-from-jpg result.

    


    Why is this happening and how can I avoid changing image data until I'm ready to encode ?

    


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